World IPv6 Day is an initiative by Google, Facebook and other popular websites, taking place on Wednesday June 8th, 2011: http://isoc.org/wp/worldipv6day

On that day, these sites and many others will enable IPv6 on their websites, for a 24 hour period.

If you are interested in participating by enabling IPv6 on your website, HEAnet is here to help you...

This affects a fraction of one percent of users with poorly configured setups, and the World IPv6 Day is an effort to expose these problems in a managed way.

The two main causes of the problem are:

- incorrectly configured machines on an IPv4 only network, or

- an incorrectly configured IPv6 network

In the case of a misconfigured machine, the test must be run on the user's machine, and the incorrect configuration reversed. It should not be necessary to disable IPv6, as it is likely that there is an incorrectly configured tunnel set up on the machine.

In the case of a misconfigured IPv6 network, the problem is solved by restoring full IPv6 access.

As this might result in users' machines having problems accessing Google, Youtube, Facebook and other sites on June 8th, we think it might be good to communicate this event to your users and reserve time to resolve possible problems in case they pop up. HEAnet is of course happy to help however we can in accordance with our IPv6 strategy.

While we expect the incidence of problems within our customers' networks to be low, reducing this risk is an important step to wider deployment and ultimately to an independent IPv6 service. As it currently stands, if any of your users encounter either problem on World IPv6 Day, it is likely that they are currently unable to access many HEAnet services.

There are tests that can be run in advance of June 8th, such as that seen on test-ipv6.com. I should note that some of the websites  may choose to continue to serve IPv6 following the day itself - so far every large scale test (including, for example, heise.de) has led to a permanent deployment.
 
As always, if you would like further information, please feel free to contact me dave.wilson@heanet.ie or the NOC at noc@heanet.ie.